Globalization and land-use transitions in Latin America

Current socioeconomic drivers of land-use change associated with globalization are producing two contrasting land-use trends in Latin America. Increasing global food demand (particularly in Southeast Asia) accelerates deforestation in areas suitable for modern agriculture (e.g., soybean), severely threatening ecosystems, such as Amazonian rain forests, dry forests, and subtropical grasslands. Additionally, in the coming decades, demand for biofuels may become an emerging threat. In contrast, high yields in modern agricultural systems and rural–urban migration coupled with remittances promote the abandonment of marginal agricultural lands, thus favoring ecosystem recovery on mountains, deserts, and areas of poor soils, while improving human well-being. The potential switch from production in traditional extensive grazing areas to intensive modern agriculture provides opportunities to significantly increase food production while sparing land for nature conservation. This combination of emerging threats and opportunities requires changes in the way the conservation of Latin American ecosystems is approached. Land-use efficiency should be analyzed beyond the local-based paradigm that drives most conservation programs, and focus on large geographic scales involving long-distance fluxes of products, information, and people in order to maximize both agricultural production and the conservation of environmental services.Fil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; ArgentinaFil: Mitchell, Aide. Universidad de Puerto Rico; Puerto Ric

Against consensus: Findings that jeopardize the foundations of eco-alarmism

Los avances del conocimiento se nutren fuertemente del disenso. Al dificultar que las ideas que emergen de nuevas investigaciones reemplacen a las dominantes, el sesgo confirmatorio limita el crecimiento y el desarrollo de las comunidades científicas. Presento cuatro grupos de hallazgos que desafían ideas dominantes y resilientes (consensos) en la comunidad de ecólogos: 1) la fragmentación de hábitat generalmente no resulta en pérdidas de biodiversidad a escala de paisaje, 2) las invasiones por especies exóticas contribuyen al aumento de la biodiversidad de las comunidades vegetales y, posiblemente, a una explosión de diversificación a escala global, 3) la productividad primaria del planeta aumenta, la superficie global de bosques no disminuye, la desertificación y las zonas quemadas no se expanden (no hay una ‘degradación’ generalizada de los ecosistemas), y 4) la agricultura orgánica y la mezcla de sistemas productivos con sistemas naturales en general resultan en menores rendimientos agrícolas, lo que (en contraste, por ejemplo, con los cultivos transgénicos) tiende a aumentar la demanda de tierras para agricultura, en desmedro de los ecosistemas naturales, de su biodiversidad y de sus servicios ecosistémicos. Propongo cinco mecanismos hipotéticos no excluyentes para explicar las dificultades de la comunidad científica para aceptar y enriquecerse de las consecuencias teóricas y aplicadas de estos hallazgos: el conservadorismo intelectual, las preferencias estéticas e ideológicas y la influencia de poderes político-institucionales y económicos. El desafío a ideas dominantes en base a nuevos datos debería implicar la readaptación de las agendas científicas y políticas que las tenían como sustento. Cuanto antes eso ocurra, más rápido avanzará la ciencia y más acertadas serán las políticas ambientales. Sugiero que para esto se necesita una agenda científica y educativa orientada a fomentar el espíritu crítico y contrarrestar los efectos del sesgo confirmatorio en la comunidad de ecólogos.Dissent is a source of scientific progress. Confirmatory bias in scientific communities limits their growth and development by making it difficult for dominant ideas to be replaced those emerging from new research. I present four groups of findings that challenge well established dominant views (consensus) in the community of ecologists: 1) habitat fragmentation does not generally result in biodiversity losses at the landscape scale, 2) non-native species invasions contribute to increases in biodiversity of plant communities and may even contribute to a diversification explosion during the Anthropocene, 3) planetary primary productivity is increasing, the global area of forests is not decreasing, desertification and burnt area are not expanding (there is no generalized ‘degradation’ of ecosystems), and 4) organic agriculture and landscapes mixing agriculture with (semi) natural ecosystems generally result in decreases in yield, which (in contrast, for example, with GMO-based agriculture) increases the demand of land, further threatening biodiversity and ecosystem services of natural ecosystems. I propose five non-exclusive hypothetical mechanisms to explain the confirmatory bias in ecology: intellectual conservatism, aesthetic and ideological preferences, and the influence of political-institutional and economic power. Challenging established consensus on the basis of new information should imply disruptive changes in the scientific and political agendas which had them as their foundation. The earlier this happens, the faster science will advance and the more effective environmental policies will be. In order to make this happen, I suggest the scientific and educational agenda should be specifically directed to counter the confirmatory bias by promoting critical thinking.Fil: Grau, Hector Ricardo. Universidad Nacional de Tucumán; Argentina. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentin

Hidroecosistemas de la Puna y Altos Andes de Argentina

Los humedales son zonas en donde el agua es el principal factor que controla el ambiente así como biodiversidad asociada. Especialmente en zonas áridas como la Puna, estos sistemas son de enorme importancia para la biodiversidad y las poblaciones locales que dependen de los servicios ecosistémicos que éstos proveen. En éste trabajo presentamos un mapeo basado en clasificación de imágenes satelitales de los principales humedales de un área de 14.3 millones de ha de la Puna argentina: salares, lagos y lagunas y vegas. En base a esa información cuantificamos y caracterizamos éstos sistemas desde una perspectiva regional de uso del territorio y conservación. Nuestro análisis reporta 866.580 ha de humedales repartidos en 654.076 ha de salares (4,6% de la superficie del área de estudio), 40.486 ha de cuerpos de agua (0,28%), 61.123 ha de vega salitrosa (0,43%) y 110.895 ha de vegas (0.78%). A su vez la unión de áreas de diferentes clases colindantes resultó en 15 complejos de ?hidroecosistemas? que totalizan 634.851 ha, los cuales cuentan con zonas de transición entre clases que consideramos fluctuarán entre una y otra de acuerdo a la respuesta de los diferentes humedales a cambios climáticos estacionales y/opresiones antrópicas. Consideramos que la información básica del inventario de humedales y la consideración de los mismos como sistemas complejos funcionales en ?hidroecosistemas? son un aporte relevante a la conservación y manejo de estos ecosistemas de alto valor ecológico, económico, social y cultural.Wetlands are areas where water is the primary factor controlling ecological functions. Especially in arid areas such as the Puna, these systems are extremely important for biodiversity and local populations that depend on ecosystem services these wetlands provide. Here, we present a map of wetlands based on satellite images classification of an area of 14.3 million ha in the Argentine Puna: salt flats, lakes and ponds and peatbogs. Based on this information, we quantify and characterize these systems from a regional perspective of land use and conservation. We report 866,580 ha of wetlands spread over 654,076 ha of salt flats (4.6% of the study area surface), 40,486 ha of water bodies (0.28%), 61,123 ha of “salty peatbogs” (0.43%) and 110, 895 ha of peatbogs (0.78%). In turn, the union of neighboring areas of different classes resulted in 15 complexes “hydro-ecosystems” totaling 634,851 ha, which have transitional areas between classes that fluctuate between them according to the response of different wetlands to seasonal weather changes and /or anthropic impact. This wetland inventory and its consideration as complex systems as functional “hydro-ecoystems” are a relevant contribution to the conservation and management of these ecosystems of high ecological, economic, social and cultural value; and could specifically contribute to the currently discussed wetlands law of Argentina.Fil: Izquierdo, Andrea Elisa. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Ecología Regional; ArgentinaFil: Foguet, Javier. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Ecología Regional; ArgentinaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentin

The legacy of European urbanization in southern cone of South America: An approach for the study of the history of teleconnections on territorial ecology

Analizamos la potencial influencia histórica de las ciudades fundadas a partir de la colonización europea sobre el territorio del cono sur sudamericano. Para ello describimos los patrones temporales de fundación de ciudades, elaboramos mapas del área influencia potencial de núcleos urbanos en base a su fecha de fundación y caracterizamos las ecorregiones de acuerdo con su historia de influencia urbana. En Chile, Paraguay y Argentina, las ciudades se fundaron mayormente antes de 1650 (inicio de la colonización española) y posteriormente a 1850 (durante la consolidación de los estados nacionales). En Uruguay y en el sur de Brasil, la colonización ocurrió principalmente entre 1650 y1850. El patrón bimodal del sector oeste se refleja también en las ecorregiones del Monte, el Chaco Semiárido y el Chaco Húmedo. El centro-oeste y noroeste del área de estudio incluye ecorregiones ambientalmente muy distintas (la Puna, las Yungas y el Matorral chileno), pero con una historia común de influencia temprana de ciudades fundadas en el siglo XVI. En contraste, las ecorregiones de la Patagonia muestran una escasa y tardía influencia urbana sobre el territorio a partir de fines del siglo XIX. Las ecorregiones del este, las Pampas y el Bosque Atlántico se caracterizan por fechas intermedias de colonización. Entre los procesos ecológicos potencialmente asociados a estos patrones se destacan: 1) la historia de agricultura y, principalmente, ganadería, y sus potenciales efectos ecológicos, 2) las perturbaciones asociadas a la colonización, temporalmente discretas, pero con efectos ecológicos duraderos (e.g., pulsos de fuego y epidemias), 3) el efecto retardado de la fundación temprana como condicionante del tamaño urbano actual, que, a su vez, influye sobre las transiciones ecológicas y la invasión de especies, y 4) la aparición de ‘nichos socioecológicos’ distintivos en las zonas de colonización tardía (e.g., los menonitas en el Chaco). Este estudio brinda una visión integradora y metodológicamente promisoria para analizar la historia ecológica de las teleconexiones, clave del funcionamiento del Antropoceno.We analyzed the potential historical influence of cities in the South American Southern Cone. To do so, we described temporal patterns of cities´ foundations; we built maps of potential influence of urban centers and characterized ecoregions according to their history of ‘influential’ cities. In Chile, Paraguay and Argentina, cities were mostly founded prior to 1650 (early Spanish colonization) and after 1850 (consolidation of national states). In Uruguay and Brazil, colonization occurred mostly between 1650 and 1850. The bimodal pattern observed in the western side of the study area is also reflected in the Monte, Arid Chaco and Humid Chaco ecoregions. The center-west and northwest of the area include ecoregions which are environmentally very different (Puna, Yungas, Chilean matorral), but have a common early history of cities´ influence during the 16th century. In contrast, the ecoregions of the Patagonia show low and late urban influence, starting in the 19th century. The ecoregions of the east (Pampas and Atlantic forest) are characterized by intermediate colonization dates. Among the ecological processes potentially associated with these patterns of cities foundation, we identify the following: 1) history of agriculture and, most importantly, livestock herbivory and its ecological consequences, 2) short term perturbations with longlasting effects (e.g., pulses of fire activity, human diseases), 3) the delayed effect of early cities foundations as cause of current urban size, which in turns influences ecological transitions and exotic species invasions, and 4) the emergence of novel ‘social-ecological’ niches in areas of late colonization (e.g., Mennonites in the Chaco). This study provides an integrative and promising methodological approach to analyze the ecological history of land-based teleconnections, a key for the functioning of the Anthropocene.Fil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Foguet, Javier. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentin

Extent and originality in the creation of national parks in relation to government and economical changes in Argentina

Argentina tiene una historia prolongada de creación de áreas protegidas que permite analizar las tendencias temporales, territoriales y biogeográficas en relación a cambios macroeconómicos y políticos. En este trabajo creamos un índice que cuantifica la originalidad del aporte de cada parque nacional a la conservación en términos de su contribución a la diversidad biogeográfica. Para analizar cómo varía la creación de parques nacionales en relación a cambios político-económicos, realizamos análisis de épocas superpuestas para el periodo 1930-2004 y para los dos subperiodos de igual duración incluidos, utilizando independientemente como variables predictivas el Producto Bruto Interno y los Ingresos Relativos de la Administración Pública Nacional; y correlacionamos estas dos variables con la superficie y el índice de originalidad de los parques. Finalmente comparamos la superficie y originalidad de los parques entre distintos períodos de gobierno de Argentina, y entre periodos de gobiernos democráticos y no democráticos. Los análisis de épocas superpuestas revelaron que la creación de parques está precedida por un año con aumentos significativos en el Producto Bruto Interno, principalmente durante las últimas cuatro décadas, en que se observan correlaciones positivas entre indicadores económicos y creación de parques. La “Década Infame” (1930-1945) fue el periodo responsable de la mayor superficie de parques; y el período “Neoliberal” (1990-2001) de la mayor originalidad y número de parques creados. Los gobiernos no democráticos generaron la mayor superficie de parques nacionales, y los democráticos la mayor originalidad. Los resultados permiten dividir la historia de creación de parques nacionales de Argentina en dos etapas caracterizadas por patrones espaciales y mecanismos causales diferentes. En la Etapa de Defensa Nacional (1930 a mediados de 1960) se crearon parques grandes sobre límites nacionales y, dada la importancia asignada a la soberanía nacional, su creación fue relativamente independiente de excedentes económicos. En la Etapa de Diversificación Biogeográfica (mediados de 1960 a 2004) se crearon muchos parques de menor tamaño en regiones biogeográficas variadas y con creciente valor inmobiliario; enfocados en tendencias internacionales de conservación de la biodiversidad, su creación tuvo un comportamiento de “bienes de lujo”, en los que el Estado invierte cuando se encuentra con excedentes presupuestarios.Argentina has a long history of protected areas creation which allows assessing temporal, territorial and biogeographical trends in relation to macroeconomic and political changes. In this paper, we created an index to quantify the contribution of each newly created national park to the conservation of the biogeographic diversity of Argentina ecoregions. To analyze how the creation of national parks changed in relation to macroeconomic shifts, we performed superposed epoch analyses for the period 1930-2004 and for the two included subperiods with the same temporal extent, using independently two macroeconomic indicators (Gross Domestic Product and Relative Public Administration Incomes) as the independent variables, and the creation of a national park as the dependent one; and we correlated Gross Domestic Product per capita and Relative Public Administration Incomes with the extent and originality of parks. Finally, we compared extent and originality of national parks between different government periods and between groups of democratic and non-democratic periods of government. Superposed epoch analyses showed that years of creation of national parks tended to lag one year of high Gross Domestic Product growth, particularly during the last four decades, when correlation between macroeconomic variables and creation of national parks were possitive. The “Década Infame” period (1930-1945) was responsible of the major addition of national parks area, and the “Neoliberal” period (1990-2001) showed the highest originality and number of parks created. Non-democratic governments generated the largest area of national parks and democratic governments, the highest biogeographical originality. Based on these results, the history of Argentine national parks creation can be classified into two major stages characterized by different spatial patterns and causal mechanisms. During the National Defense Stage (from 1930 to the mid 1960s) large national parks where created mostly on international boundaries and, due to the priority assigned to territorial sovereignty, their creation were relatively independent of economic variables. During the Biogeographic Diversification Stage (from the mid 1960s to 2004) many smaller parks where created on diverse ecoregions with growing land price. This stage 2 followed international trends to protect biodiversity and their creation behaved as “luxury goods” in which government investments depended on financial surpluses.Fil: Marinaro Fuentes, María Sofía. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Aráoz, Ezequiel. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; Argentin

Lake fluctuations, plant productivity, and long term variability in high elevation tropical andean ecosystems

Despite the large scientific and conservation value of tropical very high elevation Andean ecosystems (above 4500 masl) little is known about environmental trends and ranges of variability. We combined satellite image analyses and dendrochronological methods to quantify changes in water balance and plant productivity of these ecosystems in northern Argentina and southern Bolivia through assessments of lake level fluctuation combined with instrumental climatic records at lower elevation; and to assess the relationships between water balance and two indices of plant productivity: tree ring width of the treelet Polylepis tarapacana and seasonal patterns of vegetation "greenness" (EVI) derived from satellite images. Between 1986 and 2007, inter-annual lake fluctuations were positively correlated with regional precipitation and de Martonne?s aridity index between, showing a decreasing trend during the period. Changes in lake size were correlated with radial growth of P. tarapacana, and with MODIS-derived annual EVI between 2001-2010; thus indicating that water balance has a significant effect on ecosystem functioning. A long term tree ring chronology indicated that recent trends of decreasing plant productivity and lakes size are still within the range of variability of the past 400 years, but such ranges may be exceeded in the coming decades if the trend persists.Fil: Carilla, Julieta. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Paolini, Leonardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Morales, Mariano Santos. Consejo Nacional de Investigaciones Científicas y Técnicas. Científico Tecnológico Mendoza. Instituto Argentino de Nivología, Glaciología y Ciencias Ambientales; Argentin

Side effects of green technologies: the potential environmental costs of Lithium mining on high elevation Andean wetlands in the context of climate change

Lithium-based batteries are the key component of booming green technologies, including hybrid electric, plug-in hybrid electric and battery electric vehicles. Nearly 80% of the global lithium resources are located in the subtropical “Puna” highlands of Argentina, Bolivia and Chile. In these arid ecosystems, most biodiversity is related to wetlands: this highly valuable biodiversity includes the emblematic native camelids, flamingos, and a rich variety of endemic plants, and other animals. Climatic trends during the past decades, and future climate models suggest persistent drying tendencies. As other mining operations, lithium exploitations of salty flats require relatively large amounts of water. We discuss the research questions and priorities to preserve these valuable ecosystems in the context of growing potential conflicts for the use of water.Fil: Izquierdo, Andrea Elisa. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Carilla, Julieta. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Casagranda, Elvira. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo. Instituto de Ecología Regional; Argentin

Effects of glossy privet's invasion on the water dynamics of the Argentinean Yungas forest

Las Yungas argentinas (bosques de montaña) tienen alta biodiversidad y un rol clave en la regulación hídrica. El ligustro (Ligustrum lucidum) es una de las especies exóticas que dominan sus bosques secundarios. Debido a sus altas tasas de crecimiento y follaje verde todo el año, se planteó la hipótesis de que la disponibilidad de agua en el suelo se reduciría en bosques de ligustro en comparación con bosques nativos, principalmente durante la época seca (invierno-primavera). Se trabajó en seis pares de parcelas de bosques nativos y bosques secundarios monodominantes de ligustro en la Sierra San Javier, Tucumán, Argentina. Se registró la humedad edáfica mediante mediciones de contenido volumétrico y potencial hídrico y se estimó la productividad de los distintos tipos de bosque mediante el índice de vegetación de diferencia normalizada (NDVI). Durante la época seca de 2011 y 2012, los suelos en ligustrales presentaron un contenido volumétrico de agua 32,5 % y 24 % y un potencial hídrico en el suelo ocho y cuatro veces menor. Se observaron mayores valores de NDVI (8,5 %) en bosques de ligustro que en bosques nativos, principalmente en las selvas localizadas a menor altura y con mayor déficit hídrico inverno-primaveral. Los resultados sugieren que el bosque de ligustro estaría consumiendo mayor cantidad de agua, sobre todo en la época seca, debido a una actividad fenológica más prolongada respecto al bosque nativo y que su invasión en las Yungas podría alterar el funcionamiento hídrico de este ecosistema.Argentinean Yungas (subtropical montane forests) have high biodiversity and play a key role in regional watershed regulation. Ligustrum lucidum (glossy privet), native of China, is one of the dominant exotic tree species in secondary forests of this ecoregion. Due to its high growth rates and green foliage throughout the year -in contrast to native forests which are partially deciduous- the hypothesis is that water availability is reduced in glossy privet forests, especially during dry season (winter-spring). Six pairs of plots both in native and secondary glossy privet dominated forests in Sierra San Javier, Tucumán, Argentina were sampled. Soil moisture, by measuring both volumetric water content and water potential, and estimated productivity of different types of forests, through normalized difference vegetation index (NDVI derived from satellite imagery), were monitored. During 2011 - 2012 dry seasons, soil volumetric water content in glossy privet forests was 32.5 % and 24 % lower than in native forests; while soil water potential was respectively eight and four times lower. In glossy privet forests NDVI values were 8.5 % higher than in native forests; particularly in lower altitude forests and those with a higher winter-spring water deficit. These results suggest that the glossy privet forest would be consuming more water, especially during the dry season, due to more prolonged phenology activity compared to native forests. In consequence, glossy privet invasion in Argentinean Yungas could alter water functioning of this ecosystem.Fil: Zamora Nasca, Lucia Belén. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; ArgentinaFil: Montti, Lia Fernanda. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Centro de Investigaciones del Bosque Atlantico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Paolini, Leonardo. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales E Instituto Miguel Lillo. Instituto de Ecología Regional; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Asymmetric forest transition driven by the interaction of socioeconomic development and environmental heterogeneity in Central America

Forest transitions (FT) have been observed in many developed countries and more recently in the developing world. However, our knowledge of FT from tropical regions is mostly derived from case studies from within a particular country, making it difficult to generalize findings across larger regions. Here we overcome these difficulties by conducting a recent (2001-2010) satellite-based analysis of trends in forest cover across Central America, stratified by biomes, which we related to socioeconomic variables associated with human development. Results show a net decrease of woody vegetation resulting from 12,201 km2 of deforestation of moist forests and 6,825 km2 of regrowth of conifer and dry forests. The Human Development Index was the socioeconomic variable best associated with forest cover change. The least-developed countries, Nicaragua and Guatemala, experienced both rapid deforestation of moist forests and significant recovery of conifer and dry forests. In contrast, the most developed countries, Panama and Costa Rica, had net woody vegetation gain and amore stable forest cover configuration. These results imply a good agreement with FT predictions of forest change in relation to socioeconomic development, but strong asymmetry in rates and directions of change largely dependent upon the biomewhere change is occurring. The FT model should be refined by incorporating ecological and socioeconomic heterogeneity, particularly inmulticountry and regional studies. These asymmetric patterns of forest change should be evaluatedwhen developing strategies for conserving biodiversity and environmental services.Fil: Redo, Daniel J.. Universidad de Puerto Rico; Puerto RicoFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Aide, T. Mitchell. Universidad de Puerto Rico; Puerto RicoFil: Clark, Matthew L.. Sonoma State University; Estados Unido

Reversals of Reforestation Across Latin America Limit Climate Mitigation Potential of Tropical Forests

Carbon sequestration through tropical reforestation and natural regeneration could make an important contribution to climate change mitigation, given that forest cover in many tropical regions increased during the early part of the 21st century. The size of this carbon sink will depend on the degree to which second-growth forests are permanent and protected from re-clearing. Yet few studies have assessed permanence of reforestation, especially not at a large spatial scale. Here, we analyzed a 14-year time series (2001–2014) of remotely sensed land-cover data, covering all tropical Latin America and the Caribbean, to quantify the extent of second-growth forest permanence. Our results show that in many cases, reforestation in Latin America and the Caribbean during the early 21st century reversed by 2014, limiting carbon sequestration. In fact, reversals of reforestation, in which some or all gains in forest cover in the early 2000s were subsequently lost, were ten times more common than sustained increases in forest cover. Had reversals of reforestation been avoided, forests could have sequestered 0.58 Pg C, over four times more carbon than we estimate was sequestered after accounting for impermanence (0.14 Pg), representing a loss of 75% of carbon sequestration potential. Differences in the prevalence of reforestation reversals across countries suggest an important role for socio-economic, political, and ecological context, with political transitions and instability increasing the likelihood of reversals. These findings suggest that national commitments to reforestation may fall short of their carbon sequestration goals without provisions to ensure long-term permanence of new forests.Fil: Schwartz, Naomi B.. University of British Columbia; CanadáFil: Aide, T. Mitchell. Universidad de Puerto Rico; Puerto RicoFil: Graesser, Jordan. University of Queensland; AustraliaFil: Grau, Hector Ricardo. Universidad Nacional de Tucumán. Instituto de Ecología Regional. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Ecología Regional; ArgentinaFil: Uriarte, María. Columbia University; Estados Unido